London -LRB- CNN -RRB- The Hatton Garden heist , as it will surely come to be known , was every safe deposit box holder 's nightmare , every movie director 's dream .

Thieves using heavy cutting equipment and rappelling gear broke into the vault of an esteemed 60-year-old safe deposit company in the heart of London over the past holiday weekend , possibly taking advantage of as many as four days to rifle through an uncounted number of safe deposit boxes . And they reportedly got away with hundreds of thousands of pounds worth of gems and cash -- even , in the educated guess of one former police official , as much as 200 million pounds , or $ 300 million .

Police were offering few details Wednesday of the robbery at Hatton Garden Safe Deposit Ltd. . Detectives on the scene were carrying out a `` slow and painstaking '' forensic examination , police said in a statement .

`` Officers anticipate the process to take approximately two days , '' the statement said . `` At this stage it is believed that approximately 60-70 safe deposit boxes were opened during the burglary . Officers are working closely with Hatton Garden Safe Deposit Ltd to establish the identities of those affected . Police will be contacting victims directly as and when they are identified . ''

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Throughout the day Wednesday , customers of the business went in and out of the premises , clearly unhappy about not being able to learn whether their boxes were among those ransacked .

Hatton Garden is a storied area in London and the heart of the city 's diamond trade . The area 's promotional website says it is home to `` the largest and most concentrated cluster of jewellery retailers in the UK '' and has been for quite some time .

`` History tells us that the old City of London had certain streets -- or quarters -- dedicated to specific types of business , '' the website says . `` The Hatton Garden area has been the epicentre of London 's jewellery trade since medieval times .

`` Today , it maintains its international reputation as the centre of London 's diamond trade . It is one of the finest and most renowned jewellery locations in the world . ''

$ 4.8 M in gold swiped from N.C. highway . But how ?

The police statement did not put a value on the amount of the haul . But numerous British news organizations put the figure in the hundreds of thousands of pounds , which translates into even more hundreds of thousands of dollars . Many of those who rent safe deposit boxes at the company are reportedly in the jewelry trade .

But Roy Ramm , a former chief of the Flying Squad , an economic crime unit of London 's Metropolitan Police Service , came up with a much higher guess .

`` I would not be surprised , given where this one is , in Hatton Garden , if 200 million pounds is around about the amount stolen , '' Ramm said on BBC Radio 4 .

Because of the long Easter weekend , police did not hear of the robbery until Tuesday morning . This may prove to be an embarrassment , as the Telegraph newspaper reported that the alarm at the business sounded Friday but , as the front and back doors still appeared locked , no action was taken .

The website of Hatton Garden Safe Deposit Ltd. says the company was founded in 1954 and offers a `` secure and cost-effective solution to store and protect important and irreplaceable personal belongings . ''

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Robbers may have taken advantage of a four-day holiday weekend

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Estimates of the value of the items taken rage from hundreds of thousands of pounds to 200 million pounds

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The heist took place in a historic heart of London 's jewelry business